Yes, the components included to ActiveX edition only work with files up to 2Gb (this is caused by certain technology limitations). We plan to remove this size limit in SBB 8 (which you have free upgrade for).

File size limitation issue in ActiveX edition has not been resolved yet. As a matter of fact, we are working on the issue at the moment and plan to make the updated components available in the future build update (in about a fortnight).

Version 10 should not have any limitations of file sizes, except ones added by filesystem, underlying classes (TFileStream) or memory sizes (if temporary streams are stored in memory, which is by default if you don't handle OnTemporaryStreamNeeded). Please clarify which code you use to handle that 6Gb file (and did you try the PGPFilesDemo), and what error do you receive.